> ## Documentation Index
> Fetch the complete documentation index at: https://docs.backant.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Logging

> Structured logging with the BackAnt Logger class.

BackAnt ships a custom `Logger` class in `api/helper/execution_tracking/Logger.py`. It wraps Python's standard `logging` module and automatically tags every log entry with the calling class and method name.

## The Logger class

```python theme={null}
import logging

logging.basicConfig(
    format="%(asctime)s - %(levelname)s - %(message)s",
    level=logging.INFO,
)

class Logger:
    def info(self, info: str): ...
    def warning(self, warning: str): ...
    def debug(self, debug: str): ...
    def exception(self, e: Exception): ...
```

A singleton `myLogger` is pre-instantiated at the bottom of the file and imported wherever logging is needed.

## Using the logger

```python theme={null}
from helper.execution_tracking.Logger import myLogger

class UsersService:
    logger = myLogger

    def create_user(self, data):
        self.logger.info(f"Creating user with email {data.get('email')}")
        try:
            user = self.users_repository.add_user(**data)
            self.logger.info(f"User created: {user.id}")
            return user
        except Exception as e:
            self.logger.warning(f"Failed to create user: {e}")
            raise
```

## Log levels

| Method                  | Level   | Use for                                    |
| ----------------------- | ------- | ------------------------------------------ |
| `myLogger.info(msg)`    | INFO    | Normal operations, created/updated/deleted |
| `myLogger.warning(msg)` | WARNING | Recoverable errors, unexpected input       |
| `myLogger.debug(msg)`   | DEBUG   | Detailed diagnostic output                 |
| `myLogger.exception(e)` | ERROR   | Full traceback — pass the exception object |

## Auto-tagging

The `Logger` inspects the call stack and prepends the calling class and method name to every message:

```
2025-01-01 12:00:00 - INFO - UsersService::create_user<Creating user with email alice@example.com>
2025-01-01 12:00:00 - WARNING - UsersRepository::add_user<Failed to write item to DB because of ...>
```

This makes it easy to trace where a log line originated without adding class names manually.

## Logger in repositories

The `Repository` base class and `DBSession` both use `myLogger` internally. Database operations are logged automatically:

```
INFO - DefaultRepository::add<Default(...) added.>
WARNING - DBSession::add<Failed to write item to DB because of ('...',)>
```

## Accessing logger in generated code

All generated services and repositories inject `myLogger` via the constructor:

```python theme={null}
myUsersRepository = UsersRepository(myDB, myLogger)
```

Access it via `self.logger` inside the class.

## Log output format

The default format is:

```
%(asctime)s - %(levelname)s - %(message)s
```

Example:

```
2025-01-01 12:00:00,123 - INFO - UsersService::get_users<Fetching all users>
```

To change the format or level, update the `basicConfig` call in `Logger.py`.